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61.
62.
Sergio Rossi Georgios Tsounis Covadonga Orejas Tirma Padrón Josep-Maria Gili Lorenzo Bramanti Núria Teixidó Julian Gutt 《Marine Biology》2008,154(3):533-545
The distribution and population structure of the eurybathic gorgonian Corallium rubrum were studied off Cap de Creus (Costa Brava, Northwestern Mediterranean Sea). Red coral is endemic to the Mediterranean Sea
and the adjacent NE Atlantic coast, where it has been over exploited for centuries. This study presents, the first quantitative
data on the spatial distribution and structure of a population extending between 50 (common SCUBA limits) and 230 m depth,
and compared it with shallow populations previously studied in the same area. Different remotely operated vehicles (ROV) and
two methodological approaches were employed during four cruises between 2002 and 2006: 1-Extensive surveys: sea to coast transects
in which red coral density and patch frequency were recorded; 2-Intensive surveys, in which parameters describing colony morphology
were recorded. Most of the hard substrate between 50 and 85 m depth was inhabited by red coral colonies, showing a patch frequency
of 8.3 ± 7.9 SD patches per 100 m-transect (total transect area: 34 m2), and within-patch colony densities of 16–376 colonies m−2 (mean of 43 ± 53 colonies m−2). Below 120 m depth red coral was less abundant, and rather than forming dense patches as in shallow water, isolated colonies
were more common. The population structure differed between sites that are easily accessible to red coral fishermen, and remote
ones (both at similar depth, 60–80 m), as colonies in easily accessible locations were smaller in height and diameter, and
showed a less developed branching pattern. At shallower locations (10–50 m depth) the population structure was significantly
different from those at deeper locations, due to the heavy harvesting pressure they are exposed to in the shallows. Twenty-five
to forty-six percentage of the deeper colonies were taller than 6 cm, while only 7–16% of the shallow water colonies exceeded
6 cm colony height. Forty-six to seventy-nine percentage of the colonies in deeper waters were large enough to be legally
harvested, while only 9–20% of the shallow water colonies met the 7 mm legal basal diameter to be collected. The branching
pattern was also better developed in deeper colonies, as up to 16% of the colonies showed fourth order branches, compared
to less than 1% of the shallow water colonies (of which 96% consisted of only one single branch). The results thus confirm
that C. rubrum populations above 50 m depth are exposed to a higher harvesting intensity than deeper populations in the same area. 相似文献
63.
64.
Animal body size is driven by habitat quality, food availability, and nutrition. Adult size can relate to birth weight, to length of the ontogenetic growth period, and/or to the rate of growth. Data requirements are high for studying these growth mechanisms, but large datasets exist for some game species. In North America, large harvest datasets exist for white-tailed deer (Odocoileus virginianus), but such data are collected under a variety of conditions and are generally dismissed for ecological research beyond local population and habitat management. We contend that such data are useful for studying the ecology of white-tailed deer growth and body size when analyzed at ordinal scale. In this paper, we test the response of growth rate to food availability by fitting a logarithmic equation that estimates growth rate only to harvest data from Fort Hood, Texas, and track changes in growth rate over time. Results of this ordinal scale model are compared to previously published models that include additional parameters, such as birth weight and adult weight. It is shown that body size responds to food availability by variation in growth rate. Models that estimate multiple parameters may not work with harvest data because they are prone to error, which renders estimates from complex models too variable to detect interannual changes in growth rate that this ordinal scale model captures. This model can be applied to harvest data, from which inferences about factors that influence animal growth and body size (e.g., habitat quality and nutritional availability) can be drawn. 相似文献
65.
Seasonal dependency of controlling factors on the phytoplankton production in Taihu Lake, China 总被引:1,自引:0,他引:1
In this study, 44 profiles of gross primary productivity(GPP) and sunlight, along with water temperature, Chlorophyll-a(Chla) and nutrients, were observed in Meiliang Bay of Taihu Lake, China, in the spring, summer, and fall seasons. Effects of water temperature, light,and nutrient concentration were examined in relation to the GPP-unit-Chla(GPP of algae per Chla). The results showed that the optimum temperature for the GPP of phytoplankton was 27.9°C, the optimal PNA-unit-Chla(photon number absorbed by phytoplankton per Chla) was 0.25(mol), and the HSCN-unit-Chla and HSCP-unit-Chla(half-saturation constants of nitrogen and phosphorus of algae per Chla) were 0.005(mg/L) and 0.0004(mg/L), respectively. The seasonal dependency of the effect of different factors on the GPP was analyzed. Compared with temperature and nutrients, light was found to be the most important factor affecting the GPP during the three seasons. The effect of temperature and nutrients on the GPP of phytoplankton has obvious seasonal change. In spring, temperature was the secondary factor affecting the GPP of phytoplankton, and the effect of nutrients may be negligible in the eutrophic lake on account of temperature limit, which showed that the GPP of algae was only affected by the physical process. In summer and fall, temperature didn't affect the GPP of algae, and the presence of nutrients was the secondary factor affecting the GPP of phytoplankton. From summer to fall, effect of phosphorus was weakened and effect of nitrogen was enhanced. 相似文献
66.
We argue that attempts to extrapolate moral motives for non‐egoistic behavior in organizational behavior often interpret results empathically or deontically, while leaving other moral motivational frames, such as the utilitarian and virtue ethical, under‐examined. We encourage the creation of experimental measures to distinguish various philosophical frames. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
67.
This paper examines the role of community-based management (CBM) in dealing with the problem of mine water pollution (MWP) in four ex-pit sites in northeast England. The outcomes of CBM can be divided into two categories: ecological (environmental improvement) and social (community improvement). The ecological outcomes range from problem recognition to investigation and remediation; the social outcomes range from community awareness to participation and enhanced cooperation. Both kinds of outcome were completely achieved in only one site (Quaking Houses). In the other three sites, varying degrees of success were achieved in each category. The main lessons learned are two-fold: first, even if CBM does not achieve its ecological aims, it may nonetheless be valuable in achieving social outcomes; second, its chances of achieving either ecological or social outcomes are linked to the resources (human, technical, financial, experiential, structural, legitimacy and network) that the community possesses. 相似文献
68.
69.
Hong Yang Xianjin Huang Jianlin Hu Julian R. Thompson Roger J. Flower 《Frontiers of Environmental Science & Engineering》2022,16(8):111
China has been committed to achieving carbon neutrality by 2060. China’s pledge of carbon neutrality will play an essential role in galvanising global climate action, which has been largely deferred by the Covid-19 pandemic. China’s carbon neutrality could reduce global warming by approximately 0.2–0.3 °C and save around 1.8 million people from premature death due to air pollution. Along with domestic benefits, China’s pledge of carbon neutrality is a “game-changer” for global climate action and can inspire other large carbon emitters to contribute actively to mitigate carbon emissions, particularly countries along the Belt and Road Initiative (BRI) routes. In order to achieve carbon neutrality by 2060, it is necessary to decarbonise all sectors in China, including energy, industry, transportation, construction, and agriculture. However, this transition will be very challenging, because major technological breakthroughs and large-scale investments are required. Strong policies and implementation plans are essential, including sustainable demand, decarbonizing electricity, electrification, fuel switching, and negative emissions. In particular, if China can peak carbon emissions earlier, it can lower the costs of the carbon neutral transition and make it easier to do so over a longer time horizon. China’s pledge of carbon neutrality by 2060 and recent pledges at the 26th UN Climate Change Conference of the Parties (COP26) are significant contributions and critical steps for global climate action. However, countries worldwide need to achieve carbon neutrality to keep the global temperature from growing beyond the level that will cause catastrophic damages globally. 相似文献
70.
Catalina Munteanu Cornelius Senf Mihai D. Nita Francesco Maria Sabatini Julian Oeser Rupert Seidl Tobias Kuemmerle 《Conservation biology》2022,36(2):e13820
High-conservation-value forests (HCVFs) are critically important for biodiversity and ecosystem service provisioning, but they face many threats. Where systematic HCVF inventories are missing, such as in parts of Eastern Europe, these forests remain largely unacknowledged and therefore often unprotected. We devised a novel, transferable approach for detecting HCVFs based on integrating historical spy satellite images, contemporary remote sensing data (Landsat), and information on current potential anthropogenic pressures (e.g., road infrastructure, population density, demand for fire wood, terrain). We applied the method to the Romanian Carpathians, for which we mapped forest continuity (1955–2019), canopy structural complexity, and anthropogenic pressures. We identified 738,000 ha of HCVF. More than half of this area was identified as susceptible to current anthropogenic pressures and lacked formal protection. By providing a framework for broad-scale HCVF monitoring, our approach facilitates integration of HCVF into forest conservation and management. This is urgently needed to achieve the goals of the European Union's Biodiversity Strategy to maintain valuable forest ecosystems. 相似文献